System and method of routing voice communications via peering networks

ABSTRACT

A method of routing voice communications is disclosed and includes receiving network event data at a telephone number mapping (ENUM) server of an originating network from a plurality of peering border elements associated with a plurality of peering communication networks. The network event data indicates a health status of each of the peering communication networks. The method also includes determining a network weight related to each of the peering communication networks based on the network event data, wherein each network weight indicates a proportion of calls that are to be routed from the originating network via the related peering communication network. The method further includes dynamically assigning a plurality of preference field values to session initiation protocol (SIP) addresses of the peering border elements within a plurality of naming authority pointer (NAPTR) records, based on the network weights.

FIELD OF THE DISCLOSURE

The present disclosure generally relates to communication networks, andmore particularly relates to routing voice communications via peeringnetworks.

BACKGROUND

Internet Protocol (IP) multimedia carriers can provide voicecommunication services and other services via IP Multimedia Subsystem(IMS) networks. One IP multimedia carrier may have multiple IP peeringrelationships with other carriers, in order to connect calls betweenoriginating and terminating devices via different carrier networks. Inthe event of congestion or other problems in one or more peering carriernetworks, a call may fail to reach its terminating device.

BRIEF DESCRIPTION OF THE DRAWINGS

It will be appreciated that for simplicity and clarity of illustration,elements illustrated in the Figures have not necessarily been drawn toscale. For example, the dimensions of some of the elements areexaggerated relative to other elements. Embodiments incorporatingteachings of the present disclosure are shown and described with respectto the drawings presented herein, in which:

FIG. 1 is a block diagram illustrating a particular embodiment of asystem to route voice communications via peering networks;

FIG. 2 is a block diagram illustrating a second particular embodiment ofa system to route voice communications via peering networks;

FIG. 3 is a flow diagram illustrating a particular embodiment of amethod of routing voice communications via peering networks;

FIG. 4 is a flow diagram illustrating a second particular embodiment ofa method of routing voice communications via peering networks;

FIG. 5 is a block diagram illustrating examples of naming authoritypointer (NAPTR) records; and

FIG. 6 is a block diagram illustrating a particular embodiment of ageneral computer system.

The use of the same reference symbols in different drawings indicatessimilar or identical items.

DETAILED DESCRIPTION OF THE DRAWINGS

The numerous innovative teachings of the present application will bedescribed with particular reference to the presently preferred exemplaryembodiments. However, it should be understood that this class ofembodiments provides only a few examples of the many advantageous usesof the innovative teachings herein. In general, statements made in thespecification of the present application do not necessarily delimit anyof the claimed systems, methods or computer-readable media. Moreover,some statements may apply to some disclosed features but not to others.

FIG. 1 illustrates a particular embodiment of a system 100 to routevoice communications via peering networks. The system 100 includes aplurality of peering Voice-over Internet Protocol (VoIP) carriernetworks. For example, the plurality of peering carrier networks includea Carrier A network 102 that communicates with a Carrier B network 112,a Carrier C network 122 and a Carrier D network 132. While four peeringcarrier networks are illustrated, the plurality of peering carriernetworks can include fewer than or more than four networks. In addition,the Carrier A network 102 communicates with a first VoIP access network142, while the Carrier B network 112, the Carrier C network 122 and theCarrier D network 132 each communicate with a second VoIP access network152.

Each of the carrier networks includes at least one peering borderelement (PBE). For example, the Carrier A network 102 includes a firstpeering border element (PBE A) 108, the Carrier B network 112 includes asecond peering border element (PBE B) 118, the Carrier C network 122includes a third peering border element (PBE C) 128, and the Carrier Dnetwork 132 includes a fourth peering border element (PBE D) 138. In oneembodiment, each carrier network includes elements of an IP MultimediaSubsystem (IMS). For instance, the Carrier A network 102 includes atelephone number mapping (ENUM) server 104 that stores naming authoritypointer (NAPTR) records related to various subscriber devices, and aserving call session control function (S-CSCF) network element 106 thatfunctions as a session initiation protocol (SIP) server to allowsubscriber devices to register with the Carrier A network 102. Eachcarrier network can include at least one S-CSCF, at least one proxy CSCF(P-CSCF), at least one interrogating CSCF (I-CSCF), at least one homesubscriber server (HSS), at least one application server, at least oneENUM server, or any combination thereof.

The S-CSCF 106 is adapted to receive a call connection requestoriginating from the caller VoIP phone 140 via the first VoIP accessnetwork 142. The connection request includes an E.164 number associatedwith a destination device, such as the called VoIP phone 150. In anillustrative embodiment, the connection request can be received at theS-CSCF 106 via an originating P-CSCF (not shown) that serves as a firstpoint of contact between the Carrier A network 102 and the caller VoIPphone 140. The S-CSCF 106 is adapted to translate the E.164 number to afully qualified domain name (FQDN). For example, the S-CSCF 106 cantranslate the telephone number +1-512-222-5485 into the FQDN5.8.4.5.2.2.2.2.1.5.1.e164.arpa.

Further, the terminating S-CSCF 106 is adapted to send a request to theENUM server 104 for NAPTR records related to the FQDN. The S-CSCF 106 isadapted to receive a plurality of NAPTR records related to the calledVoIP phone 150 from the ENUM server 104 in response to the request. TheS-CSCF 106 is adapted to send a SIP INVITE communication to the calledVoIP phone 150 via one of the switches PBE B 118, PBE C 128 or PBE D138, based on information in the NAPTR records received from the ENUMserver 104.

The NAPTR records received from the ENUM server 104 include a pluralityof NAPTR records related to the switches PBE B 118, PBE C 128 and PBE D138. Each NAPTR record in this plurality includes a SIP address of oneof the switches, as well as an order field value and a preference fieldvalue that can be used by the S-CSCF 106 to determine whether the switchis to be used to route the call from the caller VoIP phone 140 to thecalled VoIP phone 150. Examples of NAPTR records are illustrated in FIG.5.

In an illustrative embodiment, the S-CSCF 106 is adapted to route a callto a SIP address of a PBE that is associated with the lowest combinationof order field and preference field values. For instance, if order fieldand preference field values in a NAPTR record having a SIP address ofPBE B 118 are [100,10], and order field and preference field values inNAPTR records having SIP addresses of PBE C 128 and PBE D 138 are[100,20] and [100,30], respectively, the combination of the order fieldvalue and preference field value associated with the SIP address of PBEB 118 is lower (110) than the combinations associated with SIP addressesof PBE C 128 and PBE D 138 (120 and 130, respectively). Hence, theS-CSCF 106 can be adapted to route a call bound for the called VoIPphone 150 via PBE B 118. In an alternative embodiment, a call can berouted to the SIP address of a PBE associated with a lowest combinationof order field and preference field values, where the preference fieldvalues are constant and the order field values vary. In yet anotherembodiment, a call can be routed to the SIP address of a PBE associatedwith a lowest combination of order field and preference field values,the order field and preference field values may both vary.

The ENUM server 104 is adapted to periodically extract network eventdata from PBE B 118, PBE C 128, and PBE D 138. The network event datacan relate to network congestion, the function of network elements, thefunction of software applications, other indicia of a network healthstatus, or a combination thereof. Examples of network event data caninclude delays in call setup, dropped calls, packet loss, and otherindicia. The ENUM server 104 is adapted to determine, based on thenetwork event data, whether each of the Carrier B network 112, theCarrier C network 122, and the Carrier D network 132 is operating withinpre-defined parameters. Such parameters can be received at the ENUMserver 104 from a network administrator or other user.

The ENUM server 104 is adapted to determine weights associated with theCarrier B network 112, the Carrier C network 122, and the Carrier Dnetwork 132, based on the network event data. In one embodiment, theENUM server 104 is adapted to determine network weights that reflect aproportion of calls that can be routed to each of the Carrier B network112, the Carrier C network 122, and the Carrier D network 132, such thatcongestion or delay within each of Carrier B network 112, the Carrier Cnetwork 122, and the Carrier D network 132 is equal or approximatelyequal, given the presence or severity of any problems in the Carrier Bnetwork 112, the Carrier C network 122, the Carrier D network 132, orany combination thereof.

For instance, when the Carrier B network 112, the Carrier C network 122and the Carrier D network 132 are operating within pre-definedparameters, the ENUM server 140 can determine equal or approximatelyequal network weights for Carrier B network 112, the Carrier C network122 and the Carrier D network 132 (e.g., one-third each, or 0.333, 0.333and 0.334). In another example, where the Carrier B network 112 isoperating within pre-defined parameters, but the Carrier C network 122and the Carrier D network 132 are not, the ENUM server 104 can determinedifferent weights for the Carrier B network 112, the Carrier C network122 and the Carrier D network 132 (e.g., 0.85, 0.10 and 0.05).

In addition, the ENUM server 104 is adapted to configure namingauthority pointer (NAPTR) records that include session initiationprotocol (SIP) addresses of PBE B 118, PBE C 128 and PBE D 138, based onthe network weights. In one embodiment, the ENUM server 104 candynamically assign order field values and preference field values withineach of the NAPTR records, such that the S-CSCF 106 will route each callto a PBE associated with a least congested one of the Carrier B network112, the Carrier C network 122, and the Carrier D network 132, whiletaking into account one or more communication networks that may not beoperating within the pre-defined parameters. For instance, the ENUMserver 104 can be adapted to dynamically assign a lowest combination oforder field and preference field values to the least congested one ofthe Carrier B network 112, the Carrier C network 122, and the Carrier Dnetwork 132.

In a particular embodiment, the ENUM server 104 is adapted to receive aNAPTR record request from the S-CSCF 106. The NAPTR record request caninclude a FQDN or other indicator of a destination device, such as thecalled VoIP phone 150. The ENUM server 104 is adapted to retrieve NAPTRrecords related to the FQDN or other indicator identified by the NAPTRrecord request and to send the retrieved NAPTR records to the S-CSCF106. The ENUM server 104 can then re-assign order field values,preference field values, or any combination thereof, in the NAPTRrecords based on the previously determined network weights, such thatthe S-CSCF 106 will route a next call via the least congested one of theCarrier B network 112, the Carrier C network 122, and the Carrier Dnetwork 132, taking into account the network used to route the callplaced to the VoIP phone 150. The ENUM server 104 can continuedynamically assigning the order field values, preference field values,or any combination thereof, until new network weights are determined,until a new network event sample period ends, or a combination thereof.

In an illustrative embodiment, if the Carrier B network 112, the CarrierC network 122, and the Carrier D network 132 are operating withinpre-defined parameters, the ENUM server 104 can be adapted to determineequal or approximately equal weights for each of the networks, such thatcalls will be distributed evenly among the Carrier B network 112, theCarrier C network 122, and the Carrier D network 132, in a round-robinfashion. The ENUM server 104 can dynamically assign order field values,preference field values, or any combination thereof, in the NAPTRrecords, such that calls are routed evenly from the Carrier A network102 via PBE B 118, PBE C 128 and PBE D 138. For instance, the ENUMserver 104 can dynamically assign a lowest combination of order fieldand preference field values to a NAPTR record including a SIP address ofPBE B 118 for one-third of calls; to a NAPTR record including a SIPaddress of PBE C 128 for another one-third of calls; and to a NAPTRrecord including a SIP address of PBE D 138 for an additional one-thirdof calls.

Accordingly, the ENUM server 104 can be adapted to send NAPTR recordshaving a lowest combination of order field and preference field valuesassociated with a SIP address of PBE B 118 to the S-CSCF 106 in responseto one-third of NAPTR record requests; to send NAPTR records having alowest combination of order field and preference field values associatedwith a SIP address of PBE C 128 to the S-CSCF 106 in response toone-third of NAPTR record requests; and to send NAPTR records having alowest combination of order field and preference field values associatedwith a SIP address of PBE D 138 to the S-CSCF 106 in response toone-third of NAPTR record requests.

In another example, the Carrier B network 112 can be operating withinpre-defined parameters; the Carrier C network 122 can be experiencing acertain degree of congestion; and the Carrier D network 132 can beexperiencing a greater degree of congestion. The ENUM server candetermine that, due to the congestion in the Carrier C network 122 andthe Carrier D network 132, routing eighty-five percent of calls via theCarrier B network 112, routing ten percent of calls via the Carrier Cnetwork 122, and routing five percent of calls via the Carrier D network132, will result in similar or equal congestion or delay among theCarrier B network 112, the Carrier C network 122, and the Carrier Dnetwork 132 for calls routed by the S-CSCF 106.

The ENUM server 104 can be adapted to determine different weights foreach of the networks, such that eighty-five percent of calls will berouted via the Carrier B network 112; ten percent of calls will berouted via the Carrier C network 122; and five percent of calls will berouted via the Carrier D network 132. The ENUM server 104 candynamically assign order field values, preference field values, or anycombination thereof, in the NAPTR records to match the network weights.For instance, the ENUM server 104 can dynamically assign a lowestcombination of order field and preference field values to a NAPTR recordincluding a SIP address of PBE B 118 for eighty-five percent of calls;to a NAPTR record including a SIP address of PBE C 128 for ten percentof calls; and to a NAPTR record including a SIP address of PBE D 138 forfive percent of calls.

Accordingly, the ENUM server 104 can be adapted to send NAPTR recordshaving a lowest combination of order field and preference field valuesassociated with a SIP address of PBE B 118 to the S-CSCF 106 in responseto eighty-five percent of NAPTR record requests; to send NAPTR recordshaving a lowest combination of order field and preference field valuesassociated with a SIP address of PBE C 128 to the S-CSCF 106 in responseto ten percent of NAPTR record requests; and to send NAPTR recordshaving a lowest combination of order field and preference field valuesassociated with a SIP address of PBE D 138 to the S-CSCF 106 in responseto five percent of NAPTR record requests.

FIG. 2 illustrates a second particular embodiment of a system 200 toroute voice communications via peering networks. The system 200 includesa serving call session control function (S-CSCF) network element 202coupled to a telephone number mapping (ENUM) server 252. The S-CSCF 202and the ENUM server 252 also communicate with a switch, such as apeering border element (PBE) 270. The S-CSCF 202, the ENUM server 252and the PBE 270 are associated with a first carrier communicationnetwork, and the PBE 270 is adapted to communicate with PBEs of aplurality of communication networks peering with the first carriercommunication network.

The S-CSCF 202 includes processing logic 204 and memory 206 accessibleto the processing logic 204. The processing logic 204 can be coupled toone or more network interfaces 208 that are adapted to facilitatecommunication between the S-CSCF 202 and the ENUM server 252, and tofacilitate communication between the S-CSCF 202 and the PBE 270. Thememory 206 includes a plurality of modules 224, 226 and 228 that areadapted to enable the S-CSCF 202 to provide a plurality of functionswith respect to routing voice communications via peering networks. Inone embodiment, the modules 224, 226 and 228 include instructions thatare readable and executable by the processing logic 204, such as aspectsof one or more software applications, operating systems or othercomputer programs. In other embodiments, the modules 224, 226 and 228can include software instructions, hardware logic, or a combinationthereof.

The memory 206 includes a request module 224 that is executable by theprocessing logic 204 to receive a call connection request from anoriginating device, such as a caller VoIP phone. The connection requestincludes an E.164 number associated with a destination device, such as acalled party VoIP phone communicating with one of the peeringcommunication networks. The request module 224 is executable by theprocessing logic 204 to translate the E.164 number to a fully qualifieddomain name (FQDN). The memory 206 also includes an ENUM module 226 thatis executable by the processing logic 204 to send a NAPTR record requestincluding the FQDN associated with the E.164 number of the destinationdevice to the ENUM server 252. The ENUM module 226 is executable by theprocessing logic 204 to receive the requested NAPTR records from theENUM server 252.

In addition, the memory 206 includes a PBE module 228 that is executableby the processing logic 204 to select one of a plurality of switchescommunicating with the destination device, such as one of a plurality ofpeering border elements (PBEs) communicating with the PBE 270, based onthe NAPTR records received from the ENUM server 252. The PBE module 228is executable by the processing logic 204 to select a switch based on avalue included in a preference field of each NAPTR record that includesa SIP address of one of the PBEs communicating with the PBE 270. The PBEmodule 228 can be executable by the processing logic 204 to route thecall associated with the connection request via the selected PBE.

The ENUM server 252 includes processing logic 254 and memory 256accessible to the processing logic 254. The processing logic 254 can becoupled to one or more network interfaces 258 that are adapted tofacilitate communication between the ENUM server 252 and the S-CSCF 202,and to facilitate communication between the ENUM server 252 and the PBE270. The memory 256 includes a plurality of modules 260-266 that areadapted to enable the ENUM server 252 to provide a plurality offunctions with respect to routing voice communications via peeringnetworks. In one embodiment, the modules 260-266 include instructionsthat are readable and executable by the processing logic 254, such asaspects of one or more software applications, operating systems or othercomputer programs. In other embodiments, the modules 260-266 can includesoftware instructions, hardware logic, or a combination thereof.

The memory 256 includes a records module 260 to store a plurality ofnaming authority pointer (NAPTR) records. Examples of NAPTR records areillustrated in FIG. 5. In a particular embodiment, each of the NAPTRrecords is associated with a fully qualified domain name (FQDN) relatedto a subscriber device. A plurality of the NAPTR records associated witha FQDN of a subscriber device can each include a SIP address associatedwith one of a plurality of PBEs communicating with the PBE 270 and withthe subscriber device. In addition, each such NAPTR record includes anorder field value and a preference field value that can be used by theS-CSCF 202 to determine which of the plurality of PBEs communicatingwith the PBE 270 is to be used to route calls from originating devicescommunicating with the S-CSCF 202 to destination devices communicatingwith peering communication networks that include the PBEs communicatingwith the PBE 270.

The memory 256 also includes a network event module 262 that isexecutable by the processing logic 254 to periodically extract networkevent data from the plurality of PBEs communicating with the PBE 270.The network event data can relate to indicia of network health statusrelated to the peering communication networks that include the pluralityof PBEs. The network event module 262 is executable by the processinglogic 254 to determine, based on the network event data, whether each ofthe peering communication networks is operating within pre-definedparameters. A network administrator or other user may configure suchparameters.

The memory 256 includes an automatic configuration (Auto Config) module264 that is executable by the processing logic 254 to determine weightsassociated with the peering communication networks, based on the networkevent data. For example, one or more of the peering communicationnetworks may not be operating within pre-defined parameters due tonetwork congestion, hardware or software malfunction, or a combinationthereof. The Auto Config module 264 is executable by the processinglogic 254 to determine network weights that reflect intended routing ofcalls among the peering communication networks, given a presence andseverity of one or more problems in the peering communication networks.

In addition, the Auto Config module 264 is executable by the processinglogic 254 to configure naming authority pointer (NAPTR) records thatinclude session initiation protocol (SIP) addresses of the PBEs of thepeering communication networks, based on the network weights. The AutoConfig module 264 can be executable by the processing logic 254 to alteran order field value, a preference field value, or a combinationthereof, within each of the NAPTR records, such that calls will berouted to a PBE associated with a least congested one of the peeringcommunication networks, while taking into account one or morecommunication networks that may not be operating within the pre-definedparameters.

The memory 256 includes a CSCF module 266 that is executable by theprocessing logic 254 to receive a NAPTR record request from the S-CSCF202. The NAPTR record request can include a FQDN or other indicator of adestination device associated with a first call. The CSCF module 266 isexecutable by the processing logic 254 to retrieve NAPTR records relatedto the FQDN or other indicator identified by the NAPTR record requestand to send the retrieved NAPTR records to the S-CSCF 202. The AutoConfig module 264 can be executable by the processing logic 254 tore-configure the NAPTR records based on the previously determinednetwork weights, such that the S-CSCF 202 will route a next call via aleast congested one of the peering communication networks, taking intoaccount the network used to route the call placed to the destinationdevice associated with the first call.

For example, when the peering communication networks are operatingwithin pre-defined parameters, the Auto Config module 264 can beexecutable by the processing logic 254 to determine equal weights foreach of the peering communication networks, such that calls will bedistributed evenly among the peering communication networks, in around-robin fashion. Further, the Auto Config module 264 can beexecutable by the processing logic 254 to dynamically assign order fieldvalues, preference field values, or any combination thereof, in NAPTRrecords that include SIP addresses of the peering border elementsincluded in the peering communication networks, such that the S-CSCF 202routes calls evenly via the peering border elements. In one embodiment,the Auto Config module 264 can be executable by the processing logic 254to dynamically assign a lowest combination of order field and preferencefield values to a NAPTR record including a SIP address of a first PBEcommunicating with the PBE 270 for one-third of calls; to a NAPTR recordincluding a SIP address of a second PBE communicating with the PBE 270for one-third of calls; and to a NAPTR record including a SIP address ofa third PBE communicating with the PBE 270 for an additional one-thirdof calls.

Accordingly, the CSCF module 266 can be executable by the processinglogic 254 to send NAPTR records having a lowest combination of orderfield and preference field values associated with a SIP address of thefirst PBE communicating with the PBE 270 to the S-CSCF 202 in responseto one-third of NAPTR record requests; to send NAPTR records having alowest combination of order field and preference field values associatedwith a SIP address of the second PBE communicating with the PBE 270 tothe S-CSCF 202 in response to one-third of NAPTR record requests; and tosend NAPTR records having a lowest combination of order field andpreference field values associated with a SIP address of the third PBEcommunicating with the PBE 270 to the S-CSCF 202 in response toone-third of NAPTR record requests.

In another example, a first one of the peering communication networkscan be operating within pre-defined parameters; a second one of thepeering communication networks can be experiencing a certain degree ofcongestion; and a third one of the peering communication networks can beexperiencing a greater degree of congestion. The Auto Config module 264can be executable by the processing logic 254 to determine that, due tothe congestion in the second and third peering communication networks,seventy-five percent of calls are to be routed via the first peeringcommunication network, seventeen percent of calls via the second peeringcommunication network, and eight percent of calls via the third peeringcommunication network.

The Auto Config module 264 can be executable by the processing logic 254to determine different weights for each of the networks, such as aweight of 0.75 for the first peering communication network; 0.17 for thesecond peering communication network; and 0.08 for the third peeringcommunication network. Further, the Auto Config module 264 can beexecutable by the processing logic 254 to dynamically assign order fieldvalues, preference field values, or any combination thereof, in theNAPTR records, such that the S-CSCF 202 routes calls via the peeringborder elements according to the network weights. For instance, the AutoConfig module 264 can be executable by the processing logic 254 todynamically assign a lowest combination of order field and preferencefield values to a NAPTR record including a SIP address of a first PBEcommunicating with the PBE 270 for seventy-five percent of calls; to aNAPTR record including a SIP address of a second PBE communicating withthe PBE 270 for seventeen percent of calls; and to a NAPTR recordincluding a SIP address of a third PBE communicating with the PBE 270for eight percent of calls.

Accordingly, the CSCF module 266 can be executable by the processinglogic 254 to send NAPTR records having a lowest combination of orderfield and preference field values associated with a SIP address of thefirst PBE communicating with the PBE 270 to the S-CSCF 202 in responseto seventy-five percent of NAPTR record requests; to send NAPTR recordshaving a lowest combination of order field and preference field valuesassociated with a SIP address of the second PBE communicating with thePBE 270 to the S-CSCF 202 in response to seventeen percent of NAPTRrecord requests; and to send NAPTR records having a lowest combinationof order field and preference field values associated with a SIP addressof the third PBE communicating with the PBE 270 to the S-CSCF 202 inresponse to eight percent of NAPTR record requests.

FIG. 3 illustrates a particular embodiment of a method of routing voicecommunications via peering networks. At block 300, a telephone numbermapping (ENUM) server associated with an originating communicationnetwork detects that a network event sampling period has ended. Movingto block 302, the ENUM server extracts network event data from aplurality of peering border elements (PBEs), where each of the PBEs isassociated with a communication network that peers with the originatingcommunication network.

Proceeding to block 304, the ENUM server determines weights to beapplied to each of the other communication networks based on the networkevent data. Further, the ENUM server configures a plurality of namingauthority pointer (NAPTR) records that include session initiationprotocol (SIP) addresses of the PBEs, based on the network weights.Continuing to block 306, the ENUM server receives a NAPTR record requestfrom a serving call session control function (S-CSCF) network elementassociated with the originating communication network. Advancing toblock 308, the ENUM server retrieves NAPTR records related to anindicator of a destination device identified by the NAPTR recordrequest. At block 310, the ENUM server sends the retrieved NAPTR recordsto the requesting S-CSCF.

Moving to decision node 312, the ENUM server determines whether a newnetwork event sampling period has ended. If a new network event samplingperiod has ended, the method returns to block 302. Conversely, if theENUM server determines that a new network event sampling period has notended, the method proceeds to decision node 314, and the ENUM serverdetermines whether it is to re-configure the NAPTR records based on thepreviously determined network weights. For example, a lowest combinationof order field and preference field values in a plurality of NAPTRrecords associated with a destination device may be associated with apeering border element of a first peering communication network. Ifnetwork weights are equal, such that calls are to be routed evenly, orif the ENUM server otherwise determines that a next call should berouted via another peering communication network, the ENUM server maydetermine that it is to re-assign order field values, preference fieldvalues, or any combination thereof, such that the lowest combination oforder field and preference field values is associated with a peeringborder element of another peering communication network beforeresponding to a next NAPTR record request.

If the ENUM server determines that it is to re-configure the NAPTRrecords, the method proceeds to block 316, and the ENUM serverre-assigns preference field values associated with the NAPTR recordsbased on the previously determined network weights. Continuing todecision node 318, the ENUM server determines whether it has received anew NAPTR record request. If the ENUM server has not received a newNAPTR record request, the method returns to decision node 312. Whereas,if the ENUM server has received a new NAPTR record request, the methodreturns to block 308, and the ENUM server retrieves the most recentlyconfigured NAPTR records related to the destination device identified inthe new NAPTR record request.

FIG. 4 illustrates a second particular embodiment of a method of routingvoice communications via peering networks. At block 400, a serving callsession control function (S-CSCF) network element associated with anoriginating communications network receives a connection request from acaller device. In an illustrative embodiment, the S-CSCF can receive theconnection request from the caller device via a proxy CSCF (P-CSCF)associated with the originating communications network. The connectionrequest can be a session initiation protocol (SIP) INVITE communicationor other connection request that identifies a destination device andrequests a call setup between the caller device and the destinationdevice.

Moving to block 402, the S-CSCF sends a request for NAPTR recordsassociated with the destination device to a telephone number mapping(ENUM) server associated with the originating communications network. Inan illustrative embodiment, the S-CSCF can translate an E.164 number ofthe destination device, which can be received with the connectionrequest, to a fully qualified domain name (FQDN) of the destinationdevice and can request NAPTR records associated with the FQDN from theENUM server. Proceeding to block 404, the S-CSCF receives the requestedNAPTR records from the ENUM server.

Continuing to block 406, the S-CSCF selects a switch, such as a peeringborder element (PBE), associated with one of a plurality of terminatingcommunications networks that communicate with the destination device.The S-CSCF selects the switch associated with a lowest combination oforder field and preference field values in the NAPTR records, where theorder field values, preference field values, or any combination thereof,are dynamically configured by the ENUM server based on network weights.Advancing to block 408, the S-CSCF routes the call via the selectedswitch. For instance, the S-CSCF can send a SIP INVITE communication tothe destination device via a second S-CSCF associated with one of theplurality of terminating networks. The method terminates at 410.

FIG. 5 illustrates examples of naming authority pointer (NAPTR) records.A telephone number mapping (ENUM) server can return such NAPTR recordsin response to a NAPTR record request received from a serving callsession control function (S-CSCF) server or similar network element ofan IP multimedia subsystem (IMS). Each NAPTR record can relate to afully qualified domain name (FQDN) 502 of a destination device. Further,each NAPTR record includes a uniform resource indicator (URI) 510associated with a service 518.

For example, a first NAPTR record 504 includes a session initiationprotocol (SIP) URI 512 associated with a SIP service designated as“E2U+sip.” The SIP URI 518 is an address of a switch, such as a peeringborder element associated with a Carrier B network (PBE B). A secondNAPTR record 506 can include a second SIP URI 514 of a switch, such as apeering border element associated with a Carrier C network (PBE C). Athird NAPTR record 508 can include a third SIP URI 516 of a switch, suchas a peering border element associated with a Carrier D network (PBE D).

In addition, each NAPTR record includes an order field 512 and apreference field 514. The order field 512 defines an order in which theNAPTR records are to be selected for a particular service. Thepreference field 514 indicates a sequence in which NAPTR records are tobe applied to a call in the course of providing each service. Forinstance, in the first set of NAPTR records 500, the SIP URI 512 isassociated with order field and preference field values of [100,10],whereas the SIP URIs 514 and 516 are associated with order field andpreference field values of [100,20] and [100,30], respectively. AnS-CSCF can route a call via PBE B based on its lowest combination oforder field and preference field values. In the second set of NAPTRrecords 530, the SIP URI 514 is associated with a preference field valueof 10, whereas the SIP URIs 516 and 512 are associated with preferencefield values of 20 and 30, respectively. An S-CSCF can route a call viaPBE C based on its lowest combination of order field and preferencefield values. Further, in the third set of NAPTR records 540, the SIPURI 516 is associated with a preference field value of 10, whereas theSIP URIs 512 and 514 are associated with preference field values of 20and 30, respectively. The S-CSCF can route a call via PBE D based on itslowest combination of order field and preference field values.

The ENUM server dynamically assigns order field values, preference fieldvalues, or any combination thereof, in the NAPTR records to matchweights associated with peering communication networks. For example, ifthe ENUM server is adapted to assign the order field and preferencefield values according to the first set of NAPTR records 500 forone-third of calls routed by the S-CSCF; to assign the preference fieldvalues according to the second set of NAPTR records 530 for one-third ofcalls routed by the S-CSCF; and to assign the preference field valuesaccording to the third set of NAPTR records 540 for one-third of callsrouted by the S-CSCF. Accordingly, the ENUM server can return the firstset of NAPTR records 500 for one-third of NAPTR record requests receivedfrom the S-CSCF; the second set of NAPTR records 530 for one-third ofNAPTR record requests received from the S-CSCF; and the third set ofNAPTR records 540 for one-third of the NAPTR record requests receivedfrom the S-CSCF.

In another example, the Carrier B communication network can be operatingwithin pre-defined parameters; the Carrier C communication network isexperiencing a certain degree of congestion; and the Carrier Dcommunication network is experiencing a greater degree of congestion.The ENUM server can determine that, due to the congestion in the CarrierC and Carrier D communication networks, routing eighty-five percent ofcalls via the Carrier B communication network, routing ten percent ofcalls via the Carrier C communication network, and routing five percentof calls via the Carrier D communication network, will result in similaror equal congestion or delay among the Carrier B communication network,the Carrier C communication network, and the Carrier D communicationnetwork for calls routed by the S-CSCF.

The ENUM server is adapted to dynamically assign order field andpreference field values according to the first set of NAPTR records 500for eighty-five percent of calls routed by the S-CSCF; to assign orderfield and preference field values according to the second set of NAPTRrecords 530 for ten percent of calls routed by the S-CSCF; and to assignorder field and preference field values according to the third set ofNAPTR records 540 for five percent of calls routed by the S-CSCF.Accordingly, the ENUM server can return the first set of NAPTR records500 for eighty-five percent of NAPTR record requests received from theS-CSCF; the second set of NAPTR records 530 for ten percent of NAPTRrecord requests received from the S-CSCF; and the third set of NAPTRrecords 540 for five percent of the NAPTR record requests received fromthe S-CSCF.

FIG. 6 shows an illustrative embodiment of a general computer system 600including a set of instructions that can be executed to cause thecomputer system to perform any one or more of the methods or computerbased functions disclosed herein. The computer system 600 may operate asa standalone device or may be connected, e.g., using a network, to othercomputer systems or peripheral devices. In an illustrative embodiment,such standalone and peripheral devices can include, for example, sessioninitiation protocol (SIP) servers, telephone number mapping (ENUM)servers, caller devices, destination devices, peering border elements(PBEs), other network elements associated with one or more IP multimediasubsystems (IMSs) or other carrier networks, or any combination thereof,as illustrated in FIGS. 1-2.

In a networked deployment, the computer system may operate in thecapacity of a server or as a client user computer in a server-clientuser network environment, or as a peer computer system in a peer-to-peer(or distributed) network environment. The computer system 600 can alsobe implemented as or incorporated into various devices, such as apersonal computer (PC), a tablet PC, a personal digital assistant (PDA),a mobile device, a palmtop computer, a laptop computer, a desktopcomputer, a communications device, a wireless telephone, a land-linetelephone, a control system, a camera, a scanner, a facsimile machine, aprinter, a pager, a personal trusted device, a web appliance, a networkrouter, switch or bridge, or any other machine capable of executing aset of instructions (sequential or otherwise) that specify actions to betaken by that machine. In a particular embodiment, the computer system600 can be implemented using electronic devices that provide voice,video or data communication. Further, while a single computer system 600is illustrated, the term “system” shall also be taken to include anycollection of systems or sub-systems that individually or jointlyexecute a set, or multiple sets, of instructions to perform one or morecomputer functions.

The computer system 600 may include a processor 602, e.g., a centralprocessing unit (CPU), a graphics processing unit (GPU), or both.Moreover, the computer system 600 can include a main memory 604 and astatic memory 606 that can communicate with each other via a bus 608. Asshown, the computer system 600 may further include a video display unit610, such as a liquid crystal display (LCD), an organic light emittingdiode (OLED), a flat panel display, a solid state display, or a cathoderay tube (CRT). Additionally, the computer system 600 may include aninput device 612, such as a keyboard, and a cursor control device 614,such as a mouse. The computer system 600 can also include a disk driveunit 616, a signal generation device 618, such as a speaker or remotecontrol, and a network interface device 620.

In a particular embodiment as depicted in FIG. 6, the disk drive unit616 may include a computer-readable medium 622 in which one or more setsof instructions 624, e.g. software, can be embedded. Further, theinstructions 624 may embody one or more of the methods or logic asdescribed herein. In a particular embodiment, the instructions 624 mayreside completely, or at least partially, within the main memory 604,the static memory 606, and/or within the processor 602 during executionby the computer system 600. The main memory 604 and the processor 602also may include computer-readable media. The network interface device620 can provide connectivity to a network 626, e.g., a wide area network(WAN), a local area network (LAN), or other network.

In an alternative embodiment, dedicated hardware implementations, suchas application specific integrated circuits, programmable logic arraysand other hardware devices, can be constructed to implement one or moreof the methods described herein. Applications that may include theapparatus and systems of various embodiments can broadly include avariety of electronic and computer systems. One or more embodimentsdescribed herein may implement functions using two or more specificinterconnected hardware modules or devices with related control and datasignals that can be communicated between and through the modules, or asportions of an application-specific integrated circuit. Accordingly, thepresent system encompasses software, firmware, and hardwareimplementations.

In accordance with various embodiments of the present disclosure, themethods described herein may be implemented by software programsexecutable by a computer system. Further, in an exemplary, non-limitedembodiment, implementations can include distributed processing,component/object distributed processing, and parallel processing.Alternatively, virtual computer system processing can be constructed toimplement one or more of the methods or functionality as describedherein.

The present disclosure contemplates a computer-readable medium thatincludes instructions 624 or receives and executes instructions 624responsive to a propagated signal, so that a device connected to anetwork 626 can communicate voice, video or data over the network 626.Further, the instructions 624 may be transmitted or received over thenetwork 626 via the network interface device 620.

While the computer-readable medium is shown to be a single medium, theterm “computer-readable medium” includes a single medium or multiplemedia, such as a centralized or distributed database, and/or associatedcaches and servers that store one or more sets of instructions. The term“computer-readable medium” shall also include any medium that is capableof storing, encoding or carrying a set of instructions for execution bya processor or that cause a computer system to perform any one or moreof the methods or operations disclosed herein.

In a particular non-limiting, exemplary embodiment, thecomputer-readable medium can include a solid-state memory such as amemory card or other package that houses one or more non-volatileread-only memories. Further, the computer-readable medium can be arandom access memory or other volatile re-writable memory. Additionally,the computer-readable medium can include a magneto-optical or opticalmedium, such as a disk or tapes or other storage device to capturecarrier wave signals such as a signal communicated over a transmissionmedium. A digital file attachment to an e-mail or other self-containedinformation archive or set of archives may be considered a distributionmedium that is equivalent to a tangible storage medium. Accordingly, thedisclosure is considered to include any one or more of acomputer-readable medium or a distribution medium and other equivalentsand successor media, in which data or instructions may be stored.

Although the present specification describes components and functionsthat may be implemented in particular embodiments with reference toparticular standards and protocols, the invention is not limited to suchstandards and protocols. For example, standards for Internet and otherpacket switched network transmission (e.g., TCP/IP, UDP/IP, HTML, HTTP)represent examples of the state of the art. Such standards areperiodically superseded by faster or more efficient equivalents havingessentially the same functions. Accordingly, replacement standards andprotocols having the same or similar functions as those disclosed hereinare considered equivalents thereof.

The illustrations of the embodiments described herein are intended toprovide a general understanding of the structure of the variousembodiments. The illustrations are not intended to serve as a completedescription of all of the elements and features of apparatus and systemsthat utilize the structures or methods described herein. Many otherembodiments may be apparent to those of skill in the art upon reviewingthe disclosure. Other embodiments may be utilized and derived from thedisclosure, such that structural and logical substitutions and changesmay be made without departing from the scope of the disclosure.Additionally, the illustrations are merely representational and may notbe drawn to scale. Certain proportions within the illustrations may beexaggerated, while other proportions may be minimized. Accordingly, thedisclosure and the FIGs. are to be regarded as illustrative rather thanrestrictive.

The Abstract of the Disclosure is provided to comply with 37 C.F.R.§1.72(b) and is submitted with the understanding that it will not beused to interpret or limit the scope or meaning of the claims. Inaddition, in the foregoing Detailed Description of the Drawings, variousfeatures may be grouped together or described in a single embodiment forthe purpose of streamlining the disclosure. This disclosure is not to beinterpreted as reflecting an intention that the claimed embodimentsrequire more features than are expressly recited in each claim. Rather,as the following claims reflect, inventive subject matter may bedirected to less than all of the features of any of the disclosedembodiments. Thus, the following claims are incorporated into theDetailed Description of the Drawings, with each claim standing on itsown as defining separately claimed subject matter.

The above disclosed subject matter is to be considered illustrative, andnot restrictive, and the appended claims are intended to cover all suchmodifications, enhancements, and other embodiments which fall within thetrue spirit and scope of the present disclosed subject matter. Thus, tothe maximum extent allowed by law, the scope of the present disclosedsubject matter is to be determined by the broadest permissibleinterpretation of the following claims and their equivalents, and shallnot be restricted or limited by the foregoing detailed description.

What is claimed is:
 1. A method of routing voice communications, themethod comprising: receiving network event data at a telephone numbermapping server of an originating network from a plurality of peeringborder elements associated with a plurality of peering communicationnetworks, wherein the network event data indicates a health status ofeach of the peering communication networks; determining a proportion ofcalls that are to be routed from the originating network via eachpeering communication network of the peering communication networks; anddynamically assigning order field values and preference field valueswithin naming authority pointer records to session initiation protocoladdresses of each peering border element of the peering border elementsbased on routing calls to a peering communication network associatedwith the peering border element in substantially equal to the proportiondetermined for the peering communication network.
 2. The method of claim1, further comprising: detecting an end of a network event samplingperiod; and querying each of the peering border elements for the networkevent data at the end of the network event sampling period.
 3. Themethod of claim 2, further comprising: detecting the end of a secondnetwork event sampling period; receiving second network event data; anddetermining a second proportion of calls related to each of the peeringcommunication networks based on the second network event data.
 4. Themethod of claim 3, wherein the order field values and preference fieldvalues are dynamically assigned to the session initiation protocoladdresses based on the proportion of calls, until the second proportionof calls are determined.
 5. The method of claim 1, further comprising:receiving a request from a serving call session control function networkelement for the naming authority pointer records, wherein the requestidentifies a destination device communicating with the peeringcommunication networks; and sending the naming authority pointer recordsto the serving call session control function, wherein a particularcombination of an order field value and a preference field value isassigned to a SIP address of a particular peering border element towhich the S-CSCF serving call session control function is to route acall to the destination device.
 6. The method of claim 5, furthercomprising: assigning the particular combination of an order field valueand a preference field values within another naming authority pointerrecord to a second session initiation protocol address of a secondpeering border element, based on the proportions of call; receiving asecond request from the serving call session control function networkelement at the telephone number mapping server for the naming authoritypointer records; and sending the naming authority pointer records fromthe telephone number mapping server to the serving call session controlfunction, wherein the naming authority pointer records include the othernaming authority pointer record.
 7. The method of claim 5, wherein theparticular combination of an order field value and a preference fieldvalue is a lowest combination of order field and preference fieldvalues.
 8. The method of claim 5, further comprising assigning aconstant order field value to session initiation protocol addresses ofpeering border elements within the naming authority pointer records. 9.A method of routing voice communications, the method comprising: sendinga request for naming authority pointer records from a serving callsession control function network element to a telephone number mappingserver, wherein the serving call session control function and thetelephone number mapping server are associated with an originatingnetwork and wherein the request identifies a destination devicecommunicating with a plurality of peering communication networks; andreceiving a plurality of naming authority pointer records from thetelephone number mapping server at the serving call session controlfunction, wherein each naming authority pointer record includes asession initiation protocol address of a peering border elementassociated with one of the peering communication networks and wherein anorder field value and a preference field value have been dynamicallyassigned by the telephone number mapping server to the naming authoritypointer record based upon a proportion of calls to be routed to theassociated peering communication network.
 10. The method of claim 9,further comprising receiving a connection request identifying thedestination device at the serving call session control function, whereinthe request for naming authority pointer records is sent in response tothe connection request.
 11. The method of claim 9, further comprisingrouting a call to the destination device via a peering border elementwherein a session initiation protocol address of the peering borderelement is associated with a particular combination of order field andpreference field values.
 12. The method of claim 11, further comprising:sending a second request from the serving call session control functionnetwork element to the telephone number mapping server for the namingauthority pointer records; and receiving the naming authority pointerrecords from the telephone number mapping server at the serving callsession control function, wherein the particular combination of orderfield and preference field values has been dynamically assigned by thetelephone number mapping server to a second session initiation protocoladdress of a second peering border element to which the serving callsession control function is to route a call.
 13. The method of claim 12,further comprising routing the call to the second destination device viathe second peering border element.
 14. A system to route voicecommunications, the system comprising: a telephone number mapping servercomprising processing logic and memory accessible to the processinglogic, the memory including instructions executable by the processinglogic to: receive network event data from a plurality of switchesassociated with a plurality of peering communication networks, whereinthe network event data indicates a health status of each of the peeringcommunication networks; determining a proportion of calls that are to berouted from the originating network via each of the peeringcommunication networks; and dynamically assigning order field values andpreference field values within naming authority pointer records tosession initiation protocol addresses of each switch of the switchesbased on routing calls to a peering communication network associatedwith the switch in approximately the proportion determined for thepeering, communication network.
 15. The system of claim 14, wherein theswitches include a plurality of peering border elements adapted tofacilitate communication between the peering communication networks andthe originating network.
 16. The system of claim 14, wherein the memoryincludes instructions executable by the processing logic to determineequal proportions related to the peering communication networks when thenetwork event data indicates that each of the peering communicationnetworks is operating within pre-defined parameters.
 17. The system ofclaim 16, wherein the memory includes instructions executable by theprocessing logic to dynamically assign a particular combination of orderfield and preference field values to the session initiation protocoladdresses of the switches in a round-robin manner.
 18. The system ofclaim 16, wherein the telephone number mapping server is adapted toreceive a user configuration of the pre-defined parameters.
 19. Thesystem of claim 14, wherein the memory includes instructions executableby the processing logic to determine, when less than all of the peeringcommunication networks are operating within pre-defined parameters,proportions of calls indicating that a first proportion of calls are tobe routed via a first communication network, wherein the firstcommunication network is operating within pre-defined parameters, and asecond proportion of calls are to be routed via a second communicationnetwork, wherein the second communication network is not operatingwithin pre-defined parameters and the second proportion of calls is alesser proportion than the first proportion of calls.
 20. The system ofclaim 19, wherein the order and preference field values are dynamicallyassigned, such that: a particular combination of order field andpreference field values is associated with a session initiation protocoladdress of a switch of the first communication network, in a firstproportion of responses to naming authority pointer record requests sentby the telephone number mapping server to a serving call session controlfunction network element of the originating network, wherein the firstproportion of responses is approximately equal to the first proportionof calls; and the particular combination of order field and preferencefield values is associated with a second session initiation protocoladdress of a second switch of the second communication network, in asecond proportion of responses to naming authority pointer recordrequests sent by the telephone number mapping server to the serving callsession control function, wherein the second proportion of responses isapproximately equal to the second proportion of calls.
 21. A system toroute voice communications, the system comprising: a serving callsession control function network element having processing logic andmemory accessible to the processing logic, wherein the memory includesinstructions executable by the processing logic to: send a request fornaming authority pointer records to a telephone number mapping server,wherein the telephone number mapping server and the serving call sessioncontrol function are associated with an originating network and whereinthe request identifies a destination device communicating with aplurality of peering communication networks; and receive a plurality ofnaming authority pointer records from the telephone number mappingserver, wherein each of the naming authority pointer records includes asession initiation protocol address of a peering border elementassociated with one of the peering communication networks and wherein aparticular combination of order field and preference field values hasbeen dynamically assigned by the telephone number mapping server to asession initiation protocol address of a particular peering borderelement to which the serving call session function is to route a call tothe destination device based on routing calls to a peering communicationnetwork associated with the particular peering border element insubstantially equal to a proportion determined for the particularpeering communication network.
 22. The system of claim 21, wherein theserving call session control function includes an interface adapted toreceive a connection request including an E.164 number of thedestination device from a caller device, and wherein the memory includesinstructions executable by the processing logic to translate the E.164of the destination device to a fully qualified domain name of thedestination device.
 23. The system of claim 22, wherein the request fornaming authority pointer records includes the fully qualified domainname, and wherein the naming authority pointer records are associatedwith the fully qualified domain name.
 24. A non-transitorycomputer-readable medium having processor-readable instructions that areexecutable by processing logic to perform a method, the methodcomprising: receiving network event data at a telephone number mappingserver of an originating network from a plurality of peering borderelements associated with a plurality of peering communication networks,wherein the network event data indicates a health status of each of thepeering communication networks; determining a proportion of calls thatare to be routed from the originating network via each of the peeringcommunication networks; and dynamically assigning order field values andpreference field values within naming authority pointer records tosession initiation protocol addresses of each peering border element ofthe peering border elements based on routing calls to a peeringcommunication network associated with the peering border element inapproximately the proportion determined for the peering communicationnetwork.
 25. The computer-readable medium of claim 24, wherein thenetwork event data includes one of indicators of network congestion,hardware malfunction, and software malfunction.